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Add index access methods to the DBBE in preparation for adding a new

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DBBE for the btree.c module. (CVS 236)

FossilOrigin-Name: c15f6ffc4d41f30a06d750c8015226713ae0126b
This commit is contained in:
drh
2001-08-19 18:19:46 +00:00
parent 888e5e96be
commit c87fa69a29
12 changed files with 340 additions and 186 deletions
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160
src/vdbe.c
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@@ -41,7 +41,7 @@
** But other routines are also provided to help in building up
** a program instruction by instruction.
**
** $Id: vdbe.c,v 1.58 2001/04/28 16:52:42 drh Exp $
** $Id: vdbe.c,v 1.59 2001/08/19 18:19:46 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
@@ -822,7 +822,7 @@ static char *zOpName[] = { 0,
"Fcnt", "New", "Put", "Distinct",
"Found", "NotFound", "Delete", "Field",
"KeyAsData", "Key", "FullKey", "Rewind",
"Next", "Destroy", "Reorganize", "ResetIdx",
"Next", "Destroy", "Reorganize", "BeginIdx",
"NextIdx", "PutIdx", "DeleteIdx", "MemLoad",
"MemStore", "ListOpen", "ListWrite", "ListRewind",
"ListRead", "ListClose", "SortOpen", "SortPut",
@@ -2245,35 +2245,33 @@ int sqliteVdbeExec(
break;
}
/* Opcode: ResetIdx P1 * *
/* Opcode: BeginIdx P1 * *
**
** Begin treating the current data in cursor P1 as a bunch of integer
** keys to records of a (separate) SQL table file. This instruction
** causes the new NextIdx instruction push the first integer table
** key in the data.
** Begin searching an index for records with the key found on the
** top of the stack. The stack is popped once. Subsequent calls
** to NextIdx will push record numbers onto the stack until all
** records with the same key have been returned.
*/
case OP_ResetIdx: {
case OP_BeginIdx: {
int i = pOp->p1;
if( i>=0 && i<p->nCursor ){
p->aCsr[i].index = 0;
int tos = p->tos;
VERIFY( if( tos<0 ) goto not_enough_stack; )
if( i>=0 && i<p->nCursor && p->aCsr[i].pCursor ){
if( Stringify(p, tos) ) goto no_mem;
pBex->BeginIndex(p->aCsr[i].pCursor, aStack[tos].n, zStack[tos]);
p->aCsr[i].keyIsValid = 0;
}
POPSTACK;
break;
}
/* Opcode: NextIdx P1 P2 *
**
** The P1 cursor points to an SQL index. The data from the most
** recent fetch on that cursor consists of a bunch of integers where
** each integer is the key to a record in an SQL table file.
** This instruction grabs the next integer table key from the data
** of P1 and pushes that integer onto the stack. The first time
** this instruction is executed after a fetch, the first integer
** table key is pushed. Subsequent integer table keys are pushed
** in each subsequent execution of this instruction.
**
** If there are no more integer table keys in the data of P1
** when this instruction is executed, then nothing gets pushed and
** there is an immediate jump to instruction P2.
** The P1 cursor points to an SQL index for which a BeginIdx operation
** has been issued. This operation retrieves the next record number and
** pushes that record number onto the stack. Or, if there are no more
** record numbers for the given key, this opcode pushes nothing onto the
** stack but instead jumps to instruction P2.
*/
case OP_NextIdx: {
int i = pOp->p1;
@@ -2283,32 +2281,15 @@ int sqliteVdbeExec(
VERIFY( if( NeedStack(p, p->tos) ) goto no_mem; )
zStack[tos] = 0;
if( VERIFY( i>=0 && i<p->nCursor && ) (pCrsr = p->aCsr[i].pCursor)!=0 ){
int *aIdx;
int nIdx;
int j, k;
nIdx = pBex->DataLength(pCrsr)/sizeof(int);
aIdx = (int*)pBex->ReadData(pCrsr, 0);
if( nIdx>1 ){
k = *(aIdx++);
if( k>nIdx-1 ) k = nIdx-1;
int recno = pBex->NextIndex(pCrsr);
if( recno!=0 ){
p->aCsr[i].lastKey = aStack[tos].i = recno;
p->aCsr[i].keyIsValid = 1;
aStack[tos].flags = STK_Int;
}else{
k = nIdx;
}
p->aCsr[i].keyIsValid = 0;
for(j=p->aCsr[i].index; j<k; j++){
if( aIdx[j]!=0 ){
aStack[tos].i = p->aCsr[i].lastKey = aIdx[j];
p->aCsr[i].keyIsValid = 1;
aStack[tos].flags = STK_Int;
break;
}
}
if( j>=k ){
j = -1;
pc = pOp->p2 - 1;
POPSTACK;
}
p->aCsr[i].index = j+1;
}
break;
}
@@ -2317,10 +2298,9 @@ int sqliteVdbeExec(
**
** The top of the stack hold an SQL index key (probably made using the
** MakeKey instruction) and next on stack holds an integer which
** the key to an SQL table entry. Locate the record in cursor P1
** that has the same key as on the TOS. Create a new record if
** necessary. Then append the integer table key to the data for that
** record and write it back to the P1 file.
** the record number for an SQL table entry. This opcode makes an entry
** in the index table P1 that associates the key with the record number.
** But the record number and the key are popped from the stack.
*/
case OP_PutIdx: {
int i = pOp->p1;
@@ -2329,53 +2309,9 @@ int sqliteVdbeExec(
DbbeCursor *pCrsr;
VERIFY( if( nos<0 ) goto not_enough_stack; )
if( VERIFY( i>=0 && i<p->nCursor && ) (pCrsr = p->aCsr[i].pCursor)!=0 ){
int r;
int newVal;
Integerify(p, nos);
newVal = aStack[nos].i;
if( Stringify(p, tos) ) goto no_mem;
r = pBex->Fetch(pCrsr, aStack[tos].n, zStack[tos]);
if( r==0 ){
/* Create a new record for this index */
pBex->Put(pCrsr, aStack[tos].n, zStack[tos],
sizeof(int), (char*)&newVal);
}else{
/* Extend the existing record */
int nIdx;
int *aIdx;
int k;
nIdx = pBex->DataLength(pCrsr)/sizeof(int);
if( nIdx==1 ){
aIdx = sqliteMalloc( sizeof(int)*4 );
if( aIdx==0 ) goto no_mem;
aIdx[0] = 2;
pBex->CopyData(pCrsr, 0, sizeof(int), (char*)&aIdx[1]);
aIdx[2] = newVal;
pBex->Put(pCrsr, aStack[tos].n, zStack[tos],
sizeof(int)*4, (char*)aIdx);
sqliteFree(aIdx);
}else{
aIdx = (int*)pBex->ReadData(pCrsr, 0);
k = aIdx[0];
if( k<nIdx-1 ){
aIdx[k+1] = newVal;
aIdx[0]++;
pBex->Put(pCrsr, aStack[tos].n, zStack[tos],
sizeof(int)*nIdx, (char*)aIdx);
}else{
nIdx *= 2;
aIdx = sqliteMalloc( sizeof(int)*nIdx );
if( aIdx==0 ) goto no_mem;
pBex->CopyData(pCrsr, 0, sizeof(int)*(k+1), (char*)aIdx);
aIdx[k+1] = newVal;
aIdx[0]++;
pBex->Put(pCrsr, aStack[tos].n, zStack[tos],
sizeof(int)*nIdx, (char*)aIdx);
sqliteFree(aIdx);
}
}
}
pBex->PutIndex(pCrsr, aStack[tos].n, zStack[tos], aStack[nos].i);
}
POPSTACK;
POPSTACK;
@@ -2385,15 +2321,9 @@ int sqliteVdbeExec(
/* Opcode: DeleteIdx P1 * *
**
** The top of the stack is a key and next on stack is integer
** which is the key to a record in an SQL table.
** Locate the record in the cursor P1 (P1 represents an SQL index)
** that has the same key as the top of stack. Then look through
** the integer table-keys contained in the data of the P1 record.
** Remove the integer table-key that matches the NOS and write the
** revised data back to P1 with the same key.
**
** If this routine removes the very last integer table-key from
** the P1 data, then the corresponding P1 record is deleted.
** which is a record number for an SQL table. The operation removes
** any entry to the index table P1 that associates the key with the
** record number.
*/
case OP_DeleteIdx: {
int i = pOp->p1;
@@ -2402,33 +2332,9 @@ int sqliteVdbeExec(
DbbeCursor *pCrsr;
VERIFY( if( nos<0 ) goto not_enough_stack; )
if( VERIFY( i>=0 && i<p->nCursor && ) (pCrsr = p->aCsr[i].pCursor)!=0 ){
int *aIdx;
int nIdx;
int j, k;
int r;
int oldVal;
Integerify(p, nos);
oldVal = aStack[nos].i;
if( Stringify(p, tos) ) goto no_mem;
r = pBex->Fetch(pCrsr, aStack[tos].n, zStack[tos]);
if( r==0 ) break;
nIdx = pBex->DataLength(pCrsr)/sizeof(int);
aIdx = (int*)pBex->ReadData(pCrsr, 0);
if( (nIdx==1 && aIdx[0]==oldVal) || (aIdx[0]==1 && aIdx[1]==oldVal) ){
pBex->Delete(pCrsr, aStack[tos].n, zStack[tos]);
}else{
k = aIdx[0];
for(j=1; j<=k && aIdx[j]!=oldVal; j++){}
if( j>k ) break;
aIdx[j] = aIdx[k];
aIdx[k] = 0;
aIdx[0]--;
if( aIdx[0]*3 + 1 < nIdx ){
nIdx /= 2;
}
pBex->Put(pCrsr, aStack[tos].n, zStack[tos],
sizeof(int)*nIdx, (char*)aIdx);
}
pBex->DeleteIndex(pCrsr, aStack[tos].n, zStack[tos], aStack[nos].i);
}
POPSTACK;
POPSTACK;